Modern semiconductor technology is usable for forming bioelectrical devices that perform various types of bio-diagnosis. In some applications, some bio tests include controlling a diagnostic sample at one or more temperatures at different time period by different stages. For example, a molecular multiplication process, also known as polymerase chain reaction process or PCR process, includes heating a sample solution to different temperatures for separating deoxyribonucleic acid (DNA) strands in the sample solution and for synthesizing new DNA segments based on the separated DNA strains by a specific primer at a specific temperature.